Fatty acid and naphthenic acid acylated borates



United States Patent This invention relates to organic boron Compoundswhich may find use as additives for liquid hydrocarbon stocks such asmotor fuels, i.e., gasoline or jet fuel, fuel oils, and lubricatingoils. More particularly, the invention relates to borated, mon oacylatedtrimethylol alkarles and to their use as motor fuel additives.

It is Well known that during the operation of an initially cleaninternal combustion engine running on a hydrocarbon fuel, depositsgradually build up on the surfaces of the engines combustion chamber.The adverse effect of such deposits manifests itself in uncontrolledignition and a general lack of smoothness in engine operation, causedprincipally by the deposits on the combustion chamber surfacesbecomingheated to incandescence during engine operation, and igniting the fueleither before or after that portion of the cycle Where normal spark plugdischarge Would cause ignition. This phenomenon is commonly referred toas surface ignition.

The deposit problem is aggravated by 'the presence in the fuel of atetra-alkyl lead anti-knock compound, because the deposits are then nolonger essentially carbonaceous, but contain appreciable quantities oflead and lead compounds in admixture with carbonaceous material. Thesemixed deposits are more tenacious and troublesome than a purecarbonaceous deposit, despite the fact that one or more organic halidemay be present in fuel as lead scavenging agents.

It has been found that the incorporation of minor amounts of the organicboron compounds of this invention to motor fuels in some manner modifiesthe nature of the combustion chamber deposits formed, so as to decreasethe incidence of surface ignition.

Deposits are also known to build up on the surfaces of carburetorinternals, viz., carburetor Walls, throttle valve, jets, and venturi.Such deposits are believed to accumu late from contaminants borne by thecopious quantities of intake air an operating carburetor breathes. Thesituation is aggravated by prolonged engine operation in I RI! where Ris an allcyl group having from 1 to 6 carbon atoms; R and R are selectedfrom the group consisting of a hydrogen atom and an alkyl radical havingfrom 1 to 3 carbon atom; and R and R" may be the same or different inthe compound; R is selected from the group consistihg of alkyl aridalkenyl radicals haviiig from 7 to 20 carbon atoms, and naphthenylradicals having from 10 to 20 carbon atoms; and X is selected from thegroup consisting of hydrogen and R! a I 0110,11

where R, R, R", and R are defined the same as above.

The bo'ron compounds of this invention may be prepared by (l) refluxingin the presence of a solvent equimola'r portions of a trialkylol alkaneand a carboxylic acid, until the theoretical amount 'of Water to formthe moho-acylated intermediate is removed az'eotropically; and (2)bo'ra'tin'g the mono-acylat'e'd intermediate with a s toicli i'ornetricamount of bofic oxide or horic acid and again removing the vi'ater ofreaction by azeotrop'ic distillation. v

The two-step reaction is believed to proceed according to the followingrepresentations:

where R, R, R and R are defined thesam'e as above, lln connection Withthe borating step, an additional molecule of Water may be removed byazeotropic distillation to form the borate anhydride:

Br! R 0H0 where R, R, R" and R' are definedthe same as above.

The reactions may be carried out in the presence of any suitable organicsolvent, such as benzene, xylenes, toluene, catalytic reformate, neutraloil and the like. Preferred solvents are those which are normally foundin the petroleum product (be it a motor fuel or fuel oil or alubricating oil) to which the boron compound is to be added. If thesolvent does not form an azeotrope with water, enough of an azeotropicforming agent is included to remove the water azeotropically.

Example I.--B0rated, Oleated Trimethylol Propane (1) 201 grams of atrimethylol propane and 423 grams of oleic acid (a 1:1 molar ratio) weremixed together in 300 ml. of xylenes. The mixture was heated withstirring at reflux until 27 m1. of water (the theoretical amount to formthe mono-acy1ated intermediate) were removed by azeotropic distillation.

(2) 478 grams of the mono-acylated intermediate and and 74.3 grams ofboric acid (a 1:1 molar ratio) were mixed together in 240 ml. ofxylenes. The mixture was heated with stirring at reflux until 54 ml. ofwater (the theoretical amount to form the borate anhydride) were removedby azeotropic distillation. Boron analysis of the resulting productshowed 2.54% B, compared with 2.60% B theoretical.

Example II.B0rated, Nonanoated, Trimethylal Propane (1) 13.4 grams oftrimethylol propane and 15.9 grams of nonanoic acid (a 1:1 molar ratio)were mixed together in 500 ml. of xylenes. The mixture was heated withstirring at reflux until 1.8 ml. of water (the theoretical amount toform the mono-acylated intermediate) were removed by azeotropicdistillation.

(2) 27.5 grams of the mono-acylated intermediate and 6.2 grams of boricacid (a 1:1 molar ratio) were mixed together in 500 ml. of xylenes. Themixture was heated with stirring at reflux until 4.5 ml. of water (thetheoretical amount to form the borate anhydride) were removed byazeotropic distillation.

Boron analysis of the resulting product showed 3.7% B, identical totheoretical.

Example lII.Borated, Laurolated Trimethylol Ethane (1) 12.2 grams oftrimethylol ethane and 200 grams of lauric acid (a 1:1 molar ratio) weremixed together in 200 ml. of xylenes. The mixture was heated withstirring at reflux until 18 ml. of water (the theoretical amount to formthe mono-acylated intermediate) were removed by azeotropic distillation.

(2) 152 grams of the mono-acylated intermediate and 31 grams of boricacid (a 1:1 molar ratio) were mixed together in 100 ml. of xylenes. Themixture was heated with stirring at reflux until 22.5 ml. of water (thetheoretical amount to form the borate anhydride) were removed byazeotropic distillation. Boron analysis of the resulting product showed3.03% B, compared with 2.81% B theoretical.

Example IV.-B0rated, Nonanoated Trimethylol Ethane (1) 12.2 grams oftrimethylol ethane and 158.5 grams of nonanoic acid (a 1:1 molar ratio)were mixed together in 250 ml. of xylenes. The mixture was heated withStirring at reflux until 18 ml. of water (the theoretical amount to formthe monoacylated intermediate) were removed by azeotropic distillation.

(2) 197 grams of the mono-acylated intermediate and 46.3 grams of boricacid (a 1:1 molar ratio) were mixed together in 187.5 ml. of xylenes.The mixture was heated with stirring at reflux until 33.7 ml. of water(the theoretical amount to form the borate anhydride) was removed byazeotropic distillation.

It will be understood that mixtures of fatty acids may also be used inthe above preparations. Commercially available mixtures include thosederived from tallow and naturally occurring oils, such as cottonseedoil, soybean oil, coconut oil, tall oil and the like.

Example V.-B0rated, Naphthenated T rimethylol Ethane Since purenaphthenic acids are not readily available, a mixture of naphthenicacids was used in the following preparation. The mixture used wasEastmans yellow label (practical grade) naphthenic acids having aboiling point range of 160-l98 C./ 6 mm. and an average molecular Weightof 230.

(1) 134 grams of trimethylol propane and 230 grams of naphthenic acids(an approximated 1:1 molar ratio based on the average molecular weightof the naphthenic' was removed by azeotropic distillation, to form theborate l anhydride.

The reaction can similarly be carried out with a,a'-dimethyl trimethylolpropane, oa,oc'-biS isopropyl trimethylol hexane, a,a-diethyltrimethylol pentane, a,a-dibutyl trimethylol heptane, a-ethyl,a-isopropyl trimethylol ethane and the like.

Gasoline base stocks to which the organic boron compounds of thisinvention can be added are any of those conventionally used in preparinga motor gasoline for a spark-ignited internal combustion engine; such ascatalytic distillate, motor polymer, alkylate, catalytic reformate,isomerate, naphthas, etc. The gasoline will preferably contain atetra-alkyl lead compound as an anti-knock agent, and a scavengingagent. The amount of the antiknock agent will be usually at a level ofapproximately 3 ml./gal., but may range from /2 ml./gal. up to 6 mL/gal.The base gasoline may also include other common additives such. asanti-oxidants, stabilizers, solvent oils, dyes, and the like. i

The amount of organic boron compound to be added to gasoline toaccomplish the purposes of this invention may vary, and is convenientlyexpressed in terms of percentrby weight of boron. Excellent results havebeen obtained where the amount of compound is within the range of .0005to .008% boron by weight. Usually amounts greater than .1% boron byweight cannot be economically justified. The compounds may be addeddirectly to the gasoline, or as previously noted, they may be added inthe form of a liquid concentrate in the solvent used in theirpreparation, provided said solvent is compatible with the gasoline.

rIt is to be understood that various modifications of the presentinvention will occur to those skilled in the art upon reading theforegoing disclosure. It is intended that all such modifications becovered which reasonably fall within the scope of the appended claim.

This application is a division of application Serial No. 93,348 filedMarch 6, 1961.

where R is an alkyl group having from 1 to 6 carbon 10 atoms; R and Rare selected from the group consisting of a hydrogen atom and an alkylradical having from 1 to 3 carbon atoms; R is selected from the groupconsisting of alkyl and alkenyl radicals having from 7 to 20 carbonatoms and naphthenyl radicals having from 10 to 20 carbon atoms; and Xis selected from the group consisting of hydrogen and where R, R and Rand R are defined the same as above.

No references cited.

